plugin.c

OpenLdap是LDAP的开源项目

/* $OpenLDAP: pkg/ldap/servers/slapd/slapi/plugin.c,v 1.26.2.5 2007/01/02 21:44:10 kurt Exp $ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
 *
 * Copyright 2002-2007 The OpenLDAP Foundation.
 * Portions Copyright 1997,2002-2003 IBM Corporation.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted only as authorized by the OpenLDAP
 * Public License.
 *
 * A copy of this license is available in the file LICENSE in the
 * top-level directory of the distribution or, alternatively, at
 * <http://www.OpenLDAP.org/license.html>.
 */
/* ACKNOWLEDGEMENTS:
 * This work was initially developed by IBM Corporation for use in
 * IBM products and subsequently ported to OpenLDAP Software by
 * Steve Omrani.  Additional significant contributors include:
 *    Luke Howard
 */

#include "portable.h"
#include <ldap_pvt_thread.h>
#include <slap.h>
#include <slapi.h>
#include <lutil.h>

/*
 * Note: if ltdl.h is not available, slapi should not be compiled
 */
#include <ltdl.h>

static int slapi_int_load_plugin( Slapi_PBlock *, const char *, const char *, int, 
	SLAPI_FUNC *, lt_dlhandle * );

/* pointer to link list of extended objects */
static ExtendedOp *pGExtendedOps = NULL;

/*********************************************************************
 * Function Name:      plugin_pblock_new
 *
 * Description:        This routine creates a new Slapi_PBlock structure,
 *                     loads in the plugin module and executes the init
 *                     function provided by the module.
 *
 * Input:              type - type of the plugin, such as SASL, database, etc.
 *                     path - the loadpath to load the module in
 *                     initfunc - name of the plugin function to execute first
 *                     argc - number of arguements
 *                     argv[] - an array of char pointers point to
 *                              the arguments passed in via
 *                              the configuration file.
 *
 * Output:             
 *
 * Return Values:      a pointer to a newly created Slapi_PBlock structrue or
 *                     NULL - function failed 
 *
 * Messages:           None
 *********************************************************************/

static Slapi_PBlock *
plugin_pblock_new(
	int type, 
	int argc, 
	char *argv[] ) 
{
	Slapi_PBlock	*pPlugin = NULL; 
	Slapi_PluginDesc *pPluginDesc = NULL;
	lt_dlhandle	hdLoadHandle;
	int		rc;
	char		**av2 = NULL, **ppPluginArgv;
	char		*path = argv[2];
	char		*initfunc = argv[3];

	pPlugin = slapi_pblock_new();
	if ( pPlugin == NULL ) {
		rc = LDAP_NO_MEMORY;
		goto done;
	}

	slapi_pblock_set( pPlugin, SLAPI_PLUGIN_TYPE, (void *)&type );
	slapi_pblock_set( pPlugin, SLAPI_PLUGIN_ARGC, (void *)&argc );

	av2 = ldap_charray_dup( argv );
	if ( av2 == NULL ) {
		rc = LDAP_NO_MEMORY;
		goto done;
	}

	if ( argc > 0 ) {
		ppPluginArgv = &av2[4];
	} else {
		ppPluginArgv = NULL;
	}

	slapi_pblock_set( pPlugin, SLAPI_PLUGIN_ARGV, (void *)ppPluginArgv );
	slapi_pblock_set( pPlugin, SLAPI_X_CONFIG_ARGV, (void *)av2 );

	rc = slapi_int_load_plugin( pPlugin, path, initfunc, 1, NULL, &hdLoadHandle );
	if ( rc != 0 ) {
		goto done;
	}

	if ( slapi_pblock_get( pPlugin, SLAPI_PLUGIN_DESCRIPTION, (void **)&pPluginDesc ) == 0 &&
	     pPluginDesc != NULL ) {
		slapi_log_error(SLAPI_LOG_TRACE, "plugin_pblock_new",
				"Registered plugin %s %s [%s] (%s)\n",
				pPluginDesc->spd_id,
				pPluginDesc->spd_version,
				pPluginDesc->spd_vendor,
				pPluginDesc->spd_description);
	}

done:
	if ( rc != 0 && pPlugin != NULL ) {
		slapi_pblock_destroy( pPlugin );
		pPlugin = NULL;
		if ( av2 != NULL ) {
			ldap_charray_free( av2 );
		}
	}

	return pPlugin;
} 

/*********************************************************************
 * Function Name:      slapi_int_register_plugin
 *
 * Description:        insert the slapi_pblock structure to the end of the plugin
 *                     list 
 *
 * Input:              a pointer to a plugin slapi_pblock structure to be added to 
 *                     the list
 *
 * Output:             none
 *
 * Return Values:      LDAP_SUCCESS - successfully inserted.
 *                     LDAP_LOCAL_ERROR.
 *
 * Messages:           None
 *********************************************************************/
int 
slapi_int_register_plugin(
	Backend *be, 
	Slapi_PBlock *pPB )
{ 
	Slapi_PBlock	*pTmpPB;
	Slapi_PBlock	*pSavePB;
	int   		 rc = LDAP_SUCCESS;

	assert( be != NULL );

	pTmpPB = SLAPI_BACKEND_PBLOCK( be );
	if ( pTmpPB == NULL ) {
		SLAPI_BACKEND_PBLOCK( be ) = pPB;
	} else {
		while ( pTmpPB != NULL && rc == LDAP_SUCCESS ) {
			pSavePB = pTmpPB;
			rc = slapi_pblock_get( pTmpPB, SLAPI_IBM_PBLOCK, &pTmpPB );
		}

		if ( rc == LDAP_SUCCESS ) { 
			rc = slapi_pblock_set( pSavePB, SLAPI_IBM_PBLOCK, (void *)pPB ); 
		}
	}
     
	return ( rc != LDAP_SUCCESS ) ? LDAP_OTHER : LDAP_SUCCESS;
}
       
/*********************************************************************
 * Function Name:      slapi_int_get_plugins
 *
 * Description:        get the desired type of function pointers defined 
 *                     in all the plugins 
 *
 * Input:              the type of the functions to get, such as pre-operation,etc.
 *
 * Output:             none
 *
 * Return Values:      this routine returns a pointer to an array of function
 *                     pointers containing backend-specific plugin functions
 *                     followed by global plugin functions
 *
 * Messages:           None
 *********************************************************************/
int 
slapi_int_get_plugins(
	Backend *be, 		
	int functype, 
	SLAPI_FUNC **ppFuncPtrs )
{
 
	Slapi_PBlock	*pCurrentPB; 
	SLAPI_FUNC	FuncPtr;
	SLAPI_FUNC	*pTmpFuncPtr;
	int		numPB = 0;
	int		rc = LDAP_SUCCESS;

	assert( ppFuncPtrs != NULL );

	if ( be == NULL ) {
		goto done;
	}

	pCurrentPB = SLAPI_BACKEND_PBLOCK( be );

	while ( pCurrentPB != NULL && rc == LDAP_SUCCESS ) {
		rc = slapi_pblock_get( pCurrentPB, functype, &FuncPtr );
		if ( rc == LDAP_SUCCESS ) {
			if ( FuncPtr != NULL )  {
				numPB++;
			}
			rc = slapi_pblock_get( pCurrentPB,
				SLAPI_IBM_PBLOCK, &pCurrentPB );
		}
	}

	if ( numPB == 0 ) {
		*ppFuncPtrs = NULL;
		rc = LDAP_SUCCESS;
		goto done;
	}

	/*
	 * Now, build the function pointer array of backend-specific
	 * plugins followed by global plugins.
	 */
	*ppFuncPtrs = pTmpFuncPtr = 
		(SLAPI_FUNC *)ch_malloc( ( numPB + 1 ) * sizeof(SLAPI_FUNC) ); 
	if ( ppFuncPtrs == NULL ) {
		rc = LDAP_NO_MEMORY;
		goto done;
	}

	pCurrentPB = SLAPI_BACKEND_PBLOCK( be );

	while ( pCurrentPB != NULL && rc == LDAP_SUCCESS )  {
		rc = slapi_pblock_get( pCurrentPB, functype, &FuncPtr );
		if ( rc == LDAP_SUCCESS ) {
			if ( FuncPtr != NULL )  {
				*pTmpFuncPtr = FuncPtr;
				pTmpFuncPtr++;
			} 
			rc = slapi_pblock_get( pCurrentPB,
					SLAPI_IBM_PBLOCK, &pCurrentPB );
		}
	}

	*pTmpFuncPtr = NULL;


done:
	if ( rc != LDAP_SUCCESS && *ppFuncPtrs != NULL ) {
		ch_free( *ppFuncPtrs );
		*ppFuncPtrs = NULL;
	}

	return rc;
}

/*********************************************************************
 * Function Name:      createExtendedOp
 *
 * Description: Creates an extended operation structure and
 *              initializes the fields
 *
 * Return value: A newly allocated structure or NULL
 ********************************************************************/
ExtendedOp *
createExtendedOp()
{
	ExtendedOp *ret;

	ret = (ExtendedOp *)slapi_ch_malloc(sizeof(ExtendedOp));
	ret->ext_oid.bv_val = NULL;
	ret->ext_oid.bv_len = 0;
	ret->ext_func = NULL;
	ret->ext_be = NULL;
	ret->ext_next = NULL;

	return ret;
}


/*********************************************************************
 * Function Name:      slapi_int_unregister_extop
 *
 * Description:        This routine removes the ExtendedOp structures 
 *					   asscoiated with a particular extended operation 
 *					   plugin.
 *
 * Input:              pBE - pointer to a backend structure
 *                     opList - pointer to a linked list of extended
 *                              operation structures
 *                     pPB - pointer to a slapi parameter block
 *
 * Output:
 *
 * Return Value:       none
 *
 * Messages:           None
 *********************************************************************/
void
slapi_int_unregister_extop(
	Backend *pBE, 
	ExtendedOp **opList, 
	Slapi_PBlock *pPB )
{
	ExtendedOp	*pTmpExtOp, *backExtOp;
	char		**pTmpOIDs;
	int		i;

#if 0
	assert( pBE != NULL); /* unused */
#endif /* 0 */
	assert( opList != NULL );
	assert( pPB != NULL );

	if ( *opList == NULL ) {
		return;
	}

	slapi_pblock_get( pPB, SLAPI_PLUGIN_EXT_OP_OIDLIST, &pTmpOIDs );
	if ( pTmpOIDs == NULL ) {
		return;
	}

	for ( i = 0; pTmpOIDs[i] != NULL; i++ ) {
		backExtOp = NULL;
		pTmpExtOp = *opList;
		for ( ; pTmpExtOp != NULL; pTmpExtOp = pTmpExtOp->ext_next) {
			int	rc;
			rc = strcasecmp( pTmpExtOp->ext_oid.bv_val,
					pTmpOIDs[ i ] );
			if ( rc == 0 ) {
				if ( backExtOp == NULL ) {
					*opList = pTmpExtOp->ext_next;
				} else {
					backExtOp->ext_next
						= pTmpExtOp->ext_next;
				}

				ch_free( pTmpExtOp );
				break;
			}
			backExtOp = pTmpExtOp;
		}
	}
}


/*********************************************************************
 * Function Name:      slapi_int_register_extop
 *
 * Description:        This routine creates a new ExtendedOp structure, loads
 *                     in the extended op module and put the extended op function address
 *                     in the structure. The function will not be executed in
 *                     this routine.
 *
 * Input:              pBE - pointer to a backend structure
 *                     opList - pointer to a linked list of extended
 *                              operation structures
 *                     pPB - pointer to a slapi parameter block
 *
 * Output:
 *
 * Return Value:       an LDAP return code
 *
 * Messages:           None